The long term objectives of this program are to develop an improved membrane artificial lung system for long term extra corporeal gas exchange support of infants and adults. The major design goals are: 1) to optimize gas exchange efficiency using secondary flows at the blood-membrane interface, thus minimizing the surface area requirements for gas exchange; 2) to reduce prime volume and use new polymeric surfaces which reduce blood trauma and thrombosis, thus allowing reduced heparinization; and 3) to provide a limited suction level and self-pumping capability to the membrane lung, eliminating the need for the gravity-fed bladder/roller pump assembly and to further reduce priming volume. The specific aims of the Phase I project are to test the feasibility of a high-efficiency self-pumping membrane lung by developing a bench prototype to perform a series of tests aimed at assessing the degree of gas transfer enhancement and the self- pumping characteristics of the system. The minimal contacting region between blood and membrane surfaces, the reduced priming volume, and the avoidance of stagnation points in this new membrane lung, in combination with the use of improved heparin coated microporous membranes, are expected to result in minimizing platelet injury, and the requirements for blood heparinization, the major causes of hemorrhagic complications during ECMO.